As Linkara noted, for a world scoured of all life by the Marvel Zombies, later series show Earth-2149 has a surprising number of hidden human survivors. Marvel Zombies: Halloween shows that Mephisto secretly protects the survivors in order to have a population of souls to later corrupt.
Zombie-Thor has replaced Mjölnir with a makeshift hammer made out of a cinder block and a pipe. Why? His zombification has rendered him of unworthy of Mjölnir and he has been rejected by it.
Why wasn't Wolverine infected in Resurrection like the rest of the heroes? Since the Respawned are a mutated form of Brood instead of the Hunger Virus (which overwhelms healing abilities), his Healing Factor was able to purge the infection from his system like it would a normal Brood embryo.
Perhaps they were all infected as humans instead of as Hulks?
Earth-Z Sandman kills the Spider-Man of his universe after mistaking him for the zombie Spider-Man that killed the other 5 members of the Sinister Six. He clearly remembered what Electro said about skipping the theatrics and just killing Spider-Man on the spot before he gets a chance to kill someone else.
Zombie Morbius impersonates the real Morbius for about two weeks. His disguise? A latex mask. Now, even in the comic, it was kinda obvious that there was a noticeable difference between the real Morbius, who looks pretty ugly because he's a Butt-Monkey, and zombie Morbius, who looks even worse because he's an zombie and a Butt-Monkey. In that two week span, didn't anyone notice that Morbius looked a little different? Or maybe notice the smell a walking corpse must have made? Or that he looked uglier than usual? Or that his body temperature was a little colder than usual? The horror comes in when you realize that for no one to notice, Morbius, even "normal" Morbius, must be really, really ugly and smelly and cold for no one to notice that a freaking zombie replaced him!
After over forty years of angsting over his fate every time he eats somebody, why did Spider-Man never kill himself? He knows that destroying the brain will work. It is possible that the Hunger Gospel simply won't let him.
Some of the zombies try to resist the hunger and fail. While we know that a LOT of them obviously failed (Zombie Spider-Man, The Zombie Avengers, etc.), just how many exactly even bothered to make the attempt in the first place!?
Since the zombies retain their hatred of people who they hated in life, that would certainly explain why most of the zombies on-panel were superheroes and only a few super villains zombified. Granted, most of the super-villains deserved their deaths, but the point still stands in that the offscreen deaths they did receive are most likely horrifying when you take into account what the zombies do to most non-zombies they find.
Just the mere idea that Marvel Zombies is part of the Marvel Multiverse. Meaning that the damn zombie virus can jump universes should a zombie travel to another universe! It's nothing short of a miracle that anyone in the Marvel Multiverse is still alive!!
